It doesn't get more dramatic than that.
Lougheed has a history of being an outspoken critic of provincial and federal politics since leaving office in 1985. He's also let his own concern about the oil sands be known, calling the pace of development "haphazard" and a threat to the environment.
Albertans themselves will hold the key to the conflict. If they make the greening of the oil sands a top political issue, the provincial government will likely be forced to negotiate ways to address this with the feds. Greenhouse gas emissions can start to be brought under control, water diversions can be minimized, and the province can avoid turning nearly a quarter of it's landspace into an open pit oil mine. If they choose to hang their hat on their "right" to develop the oil sands "as they see fit", then Canadian greenhouse emissions will spiral, entire ecosystems will be lost, and the country will be locked in a political turf war that will last decades.
In related news, Imperial Oil announced first half net income of $1.49 billion, up from $1.43 billion for the first half of 2006.